卡巴胆碱对脓毒症大鼠肺微血管内皮细胞功能的影响

Effects of carbachol on pulmonary microvascular endothelial cell function in septic rats

目的观察卡巴胆碱对脓毒症大鼠肺微血管内皮细胞（VEC）功能的影响。方法将SPF级健康雄性SD大鼠30只随机分成三组：氯化钠注射液组（SHAM组）、脓毒症组（LPS组）、卡巴胆碱组（CBL组）。LPS组经左侧股静脉注射脂多糖（LPS）10 mg/kg，SHAM组经左侧股静脉注射等量氯化钠注射液，卡巴胆碱组在注射LPS后注射卡巴胆碱10 μg/kg。分别在各组模型制备完毕后6 h经腹主动脉取血用ELISA法检查肿瘤坏死因子-α（TNF-ɑ）水平，取右肺下叶肺组织用Real-time PCR检测SSeCKS的mRNA表达，Western blot检测各组右肺下叶肺组织E-选择素蛋白质表达水平情况，取右肺中叶行透射电镜检查。结果SHAM组表达少量的TNF-ɑ、SSeCKS、E-选择素，LPS能够上调他们的表达，CBL组TNF-ɑ、SSeCKS、E-选择素较LPS组表达降低（P〈0.05）。透射电镜结果显示CBL组肺VEC水肿和凋亡等表现较LPS组相对减轻。结论卡巴胆碱不仅可以有效抑制脓毒症大鼠血浆TNF-ɑ水平，抑制炎症反应，而且能下调肺微血管内皮细胞SSeCKS和E-选择素的表达，并减轻LPS所致的肺微血管内皮细胞超微结构改变。提示卡巴胆碱能够改善脓毒症大鼠肺微血管内皮细胞的通透性。

ObjectiveTo investigate the effects of carbachol on pulmonary microvascular endothelial cell function in septic rats.MethodsThirty healthy male SPF Sprague-Dawley rats were randomly divided into three groups： saline group （SHAME）, lipopolysaccharide group （LPS） and carbachol group （CBL）. Sepsis model was reproduced by the left femoral vein sublethal dose of lipopolysaceharide（LPS, 10 mg/kg）. Carbachol group was injected with carbachol（10 μg/kg） after injection of LPS. Tumor necrosis factor-a （TNF-ɑ） in the blood from the abdominal aorta were measured by ELISA （enzyme-linked immuno sorbent assay） method, SSeCKS from lower lobe of right lung were measured by Real-time PCR method, E-selectin from lower lobe of right lung were measured by Western blot method after injection 6 h. The middle lobe of right lung was taken for transmission electron microscope examination after injection 6 h.ResultsThe TNF-ɑ, SSeCKS and E-selectin in SHAM had low expression, but LPS can make their expression increased. The expression of TNF-ɑ, SSeCKS mRNA, and E-selectin protein in CLB group was lower than those in the LPS group（P〈0.05）. The results of transmission electron microscopy showed that VEC edema and apoptosis in CBL group relatively reduced in LPS group.ConclusionsCarbachol can not only effectively inhibite the level of TNF-ɑ in septic rats plasma, inhibit inflammation, but also down-regulate the pulmonary microvascular endothelial cells with SSeCKS and E-selectin expression, and reduce the changes of ultrastructure of VEC, indicating that carbachol can improve the permeability of pulmonary microvascular endothelial cell in septic rats.